The present invention relates generally to a mounting apparatus for mounting electronic components on a circuit board, amd more particularly to such an electronic-component mounting apparatus equipped with a laser monitoring device to monitor a lifting (floating) state of a lead wire of the electronic component such as an IC chip and an LSI chip.
Generally, electronic-component mounting apparatus are arranged such that an electronic component accommodated in a feeding section such as a tray is sucked and picked up by a suction nozzle of a picking and mounting head and then mounted on a circuit board positioned at a predetermined place by a positioning device after correction of positional divergences (slippages) of the picked-up electronic component in directions X and Y perpendicular to each other on a horizontal plane and in a direction .theta. of rotation about the axis of the electronic component itself. For mounting the electronic component onto the circuit board, the correction of the positional divergences of the electronic component allows accurate positioning of lead wires of the electronic component with respect to electrodes of the circuit board. Recently, the electronic-component mounting apparatus is additionally required to have a function to finely monitor undersirable states, such as lifting, of the lead wires of the electronic component mounted on the circuit board. Accordingly, an electronic-component mounting apparatus has been proposed which is equipped with a laser type monitoring device to monitor the lifting state of the lead wires of the electronic component with laser light. There is a problem which arises with such a laser type monitoring device, however, in that there is the possibility that the operator (operating person) is illuminated with the laser light in error. Thus, a further improvement would be required from the viewpoint of safety for the operator.